Refrigerating apparatus



March 27, 1934. E. o. sToUT REFRIGERAT'ING APPARATUS 3 Sheets-Sheet lFiled July 1, 1929 Mdm,

//5 A TTORNEYS Y INVE OR March `27, 1934. E, o, STQUTV 1,952,148

REFRIGERATING APrARATU's Filed July l, 1929 3 Sheets-Sheetv 2 BY wwwa.

f//S ATTORNEYS.

REFRIGERATING APPARATUS INVENTO a y ,zy/.s ATTORNEYS.

Patented Mar. 27, 1934` 1,952,143IA l PATENT OFFICE nErmGEaA'rmGAPPARATUS Elmer o. stout, Dayton, ohio, assigner u FrigidaireCorporation, Dayton, Ohio, a corporation of Delaware Application' AJuly1, 152e, serial No. 375,081 `z claims. (c1. sz-'12s) This inventionrelates to refrigerating apparatus and particularly to cooling units forsuch apparatus.

` One of the objects of the invention is to provide an improvedevaporator which is smooth and Y, readily cleaned, and of pleasingappearance.

Another objectl of the invention is to provide an improved fabricatedcooling unit preferably constructed of sheet metal, which will readilywithstand. abnormalhigh pressures and which provides intimate thermalcontact between the substance to be cooled and the refrigerant thereinand insures even distribution of refrigerant throughout like portionsthereof.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to theaccompanyingdrawings, wherein a preferred form of the present invention is clearlyshown.

20 In the drawings:

Fig. 1 is a front view of my improved evaporator installed in arefrigerator of a household type.

Fig. 2 is an enlarged cross sectional view thru the evaporator. Fig. 3is a sectional view of the evaporator taken on line 3-3 of Fig. 2.

Fig. 4'is a view of a plate employed in the construction of theevaporator. Fig. 5 is a view of the same plate after the initial formingope/ration has been made thereon.

Fig. 6 is a view of another plate employed in the construction of theevaporator.

Fig. 7 is a view of the plates shown in Figs. 5 and 6 secured togetherbefore being formed into the desired shape and Fig. 8 is an enlargedsectional view taken on theline8`-8ofFig.3.

Referring to the drawings, Fig. 1 discloses a section of a cabinetillustrating-the installation `of a' cooling unit made in accordancewith the invention.V The cooling unit is herein shown as an evaporatorincluding a header or tank 10 and a hollow wall enclosure 1l dependingtherefrom both of which will be more fully described herein. Brackets 13and 14 supportthe evaporator in the l cabinet and are attached to theinner lining 15 of same. Also disclosed is the insulation 16 and theouter frame work or covering 17 for the in- .stallation. An L-shapedpartition 18 fprovides\ 5o a compartment for the evaporatorand hasopention of air thru the compartment for cooling the Connections 23 and24 extend to any type of Ieings' 20 and 21 located therein for thevcircula-` ture from the evaporator dripping` on the food..

' suction valve 27 located on the valve plate has a passage way to thesuction pipe 23 having an oil over-110W hole 28 therein. Below thesuction tube is the baille 29 to prevent liquid refrigerant splashingdirectly into the tube. A liquid valve 30 is also located on the valveplate and has a liquid port or entry31 with the screen 32 and'perforated cone 33 to catch any dirt in the refrigerant and prevententry of same into the boiler. Bracket 34 supports a needle valve 35which is in turn controlled by the oat ball 36 on the float ball arm 37.A liquid refrigerant 38 preferably sulphur dioxide, is contained withinthe boiler during operation. Some oil also is Adepressions 39 and has ashort tube projecting thru the hole. 'I'he exposed partsnof the ele- 85ments thus far described and generally referred to as a boiler arecovered with a metal of high polishability, preferably chromium althoothers such as nickel might also be used. 'I'his surface, which ispreferably plated, constitutes a very smooth, hard, non-rusting, finishwhich is very easily cleaned. y l

Depending from the boiler 10 thus described ls preferably the hollowwall enclosure 11 forming a. freezing zone and adapted to receive icemaking receptacles such as icetrays. In the preferred embodiment, thehollow wall enclosure is formed of an outer sheet metal wall 50 and aninner sheet metal wall 51 preferably welded together and formed toprovide the oblong enclosure 11 as dis- 100 closed in the drawings. Theinner wall 51 is provided by forming two groups of oorrugations 52 in aflat plate (see Fig. 4) and folding this plate .along the lines A-A,B-B, C-C, on one side and along the other side in a like manner 'as atAA', 105

B'-B', C-C' to form the projections 53- (see Fig. 5)'. This plate alsohas angle iron members 54 'secured thereto, the utility of which will belater described. y f The outer wall or plate'o is provided with a llt`raised portion 56 and corrugations 57 leading therefrom in oppositedirections (see Fig. 6). The plates 50 and 51 are then secured togetherso as to provide a unitary structure as shown in Fig. 7.

,` Plate 50 is slightly wider than plate 51 and this excess width isfolded over and welded to the edge of plate 51 (see Fig. 8). After thetwo plates 50 and 51 are secured together, the structure shown in Fig. 7is folded on the lines E--E and F-F to form the top and side walls ofthe enclosure 11 and is folded along the lines G-G and I-li---H to formthe bottom wall of the oblong enclosure l1 as shown in the drawings. Theends of the structure which are folded adjacent each other at the bottomof the enclosure are butt welded together to provide a rigid unit.

The projections 53 formed in the plate 51` serve as a shelf 58 Withinthe enclosure l1 for receiving an ice tray. It is apparent from theabove description that the method of simultaneously folding the sheetmetal members 50 and 51 forms the enclosure or freezing zone 11 and theshelf 58 divides the zone into compartments 59 and 60. The corrugations52 along the under side of shelf 58, by virtue of folding the plate 51as described, communicate with the corrugations 57 in the side walls ofthe enclosure 11 and permit refrigerant to enter the interior of shelf58. The refrigerant in shelf 58 increases heat transfer from an ice traysupported by the shelf. The corrugations in plate 50 have their troughspreferably contacting with theinner wall or plate 51 and thus formingpassageways or duct channels 6l by means of theirv crests and the spacebetween the troughs in com bnation with the inner wall or plate 51. Thetroughs ofthe duct channels 61 are spot welded at convenient places orroll welded to the inner wall of plate 5l. This or some equivalentoperation is desirable to prevent bulging of the sheet metal walls ifsubjected to high pressure refrigerant.

By employing one plate having a flat surface at the points where thebends are to be made and another corrugated plate I have found thatrelatively sharp corners of an evaporator of the type shown in thedrawings can be formed without danger of closing the passages formed bythe corrugations at the corners thus produced. These passage ways extendfrom opposite sides of the raised portion or manifold 56 outwardly alongthe top of the freezing zone or enclosure ll and vertically down the twosides of the enclosure. As shown in the drawings passage ways alsoextend around the corners of the freezing zone and along the bottomthereof to a point near the ends of the structure which are weldedtogether. In the top of the enclosure are one or more and preferably twoholes 63. Collar 64 is welded with a small portion projecting thru theseholes but the larger portion of the collar projects upwardly into theindentation 39 when the enclosure is assembled to the boiler. Thiscollar 64 has interior screw threads forming a fastening means wherebythe enclosure may be attached to the boiler. A washer 65 is preferablyplaced between the collars 4t and 64 and connecting member 66 havingscrew threads thereon to cooperate with the .screw threads on collar 64constituting in combination therewith a fastening means for the boilerand enclosure. The connecting member 66 has a hollow and preferablyhexagonal passage way cooperating with the central passage way of thecollar 64 to provide means whereby the liquid refrigerant may descendinto the manifold 56 and thence into the duct channels 61 of theenclosure.

aaoaiae The manifold 56 serves as an inlet to uniformly distributeliquid refrigerant thru the duct channels 61 and also as an outlet forpermitting uniform exit of gaseous refrigerant from these channels whichextend from the manifold and encircle the enclosure 11. The corrugatedstructure provides duct channels presenting a large heat absorbingsurface that isfeasily cleaned and affords means for conveniently spotand roll welding the walls 50 and 51 of the enclosure and provides avery efficient distributing system for the liquid refrigerant about thetop, sides and bottom wall of the enclosure 11 'and in the shelf 58.

The angle iron members 54 are welded to the plate 51 and are located onthe inner wall of the compartment 60 and serve as ledges upon which theshelf may be supported when it is desired to insert two shallow icetrays into this compartment instead of the one deep tray as shown in thedrawings. The ice trays have fronts 68 secured thereto and provided withhandles. These tray fronts 68 preferably extend so close to one anotherthat no additional dividing means is necessary between the trays on thefront side of the freezing zone or enclosure l1. If desired aback 69 maybe placed on the enclosure preferably by welding corner strips 10 to therear comers of the enclosure l1 and by placing the bolts or otherfastening means 71 thru the back and corner pieces. Thus the interior ofthe freezing 105 zone or the enclosure 11 is protected from thecirculating air Within the cabinet which is normally at a relativelyhigher temperature than that within the enclosure.

The walls of freezing zone or enclosure 11 are coated with a vitreousenamel baked in a high temperature, preferably porcelain, and thisconstitutes a beautiful and easily cleaned surface for the enclosure.The tray fronts and shelves may be coated or covered also with vitreousenamel baked in a high temperature to correspond with the surface of theexterior or they may be instead covered with the same metal of highpolishability that with which the boiler is plated.

1t will thus be observed that I have provided a very eicient evaporatorwhich may be easily cleaned and which occupies a minimum amount of spacein a refrigerator cabinet. It is also apparent that the individualrefrigerant duct channels extending around the corners of the evaporatoreliminates the danger of the sheet metal walls bulging under thepressure of the refrigerant in the corners at which point the metal islikely to be weakened by the bending operation. These individual ductchannels prevent the refrigerant from applying pressure upon a largearea of the sheet metal at the weakened corners thereby providing anevaporator of increased strength. Furthermore this construction providesan 135 evaporator in which substantially the entire cooling surfacesthereof are in intimate thermal contact with liquid refrigerant.

While the form of embodiment of the invention as herein disclosed,constitutes a preferred form, 140 it is to be understood that otherforms might be adopted, all coming within the scope of the claims whichfollow.

What is claimed is as follows:

1. An evaporator comprising a sheet of metal, a 145 second sheet ofmetal separate from said rst named sheet of metal but cooperatingtherewith to provide a plurality of double walls of a freezingcompartment, said separate sheets of metal being joined together attheir corresponding ends and l50 edges and having portions thereofspaced apart to form refrigerant conveying duct means be- Itween saiddouble walls, the inner of the sheets of metal of said doublewallshaving oppositely disposed and inwardly extending reverse bent portionsformed integral therewith, each' of said reverse bent portions formingrefrigerant conveying duct means, the duct means formed by said reversebent portions being separated from one another and each being incommunication.

- tions cooperating with one another to provide a plurality of doublewalls of a freezing chamber, 'said cooperating sheet metal` portionsbeing joined at their edges and having portions'thereof between theiredges spaced apart to form refrigerant conveying duct means between saiddouble walls, the inner of the cooperating sheet metal portions lof saiddouble walls having oppositely disposed and inwardly extending reversebent portions formed integral therewith, each of said reverse bent'portions forming refrigerant conveying duct means, the duct means formedby said reverse bent portions being sepa-L rated from one another andeach being in communication with the first named duct means andextending horizontally a substantial distance inwardly of the wallsofthe freezing chamber, and said integral reverse bent portionscooperating with one another to bridge substantially the entire width ofthe freezing chamber to provide a refrigerated shelf within the chamberfor supporting a receptacle to be cooled and to divide the

